Actuator for cam phaser and cam phaser

ABSTRACT

An actuator for a cam phaser, the cam phaser including a hydraulic valve that is adjustable by the actuator, wherein the actuator is receivable at a housing section of a component that receives the cam phaser, wherein the actuator includes a retaining element and a housing with functionally relevant components, wherein the actuator is attached by the retaining element at the housing section, wherein the retaining element is configured separate from the housing, wherein safe positioning of the actuator at the housing section is provided by a section of the retaining element that supports the actuator at the housing section in a direction of an axial orientation of the actuator, and wherein a housing cover of the housing is at least partially arranged between the section of the retaining element and the housing section.

RELATED APPLICATIONS

This application is a non-provisional of U.S. provisional patentapplication 62/522,624 filed on Jun. 20, 2017.

FIELD OF THE INVENTION

The invention relates to an actuator for a cam phaser and to a camphaser.

BACKGROUND OF THE INVENTION

Cam phasers for internal combustion engines are well known. The camphaser includes a hydraulic valve with a piston that is axially moveable in a housing of the hydraulic valve and which controls a hydraulicloading of the cam phaser. controlling the cam phaser is typically donehydraulically by positioning the piston and releasing or closingconnections provided at the housing. The piston is positioned by anelectromagnetic actuator. Function specific components of the actuatorlike in particular a plunger for moving the piston and components forgenerating a magnetic field for moving the plunger are received in ahousing of the actuator. Typically the housing is specific to aninternal combustion engine and configured to be received at a housingsection of the internal combustion engine so that a plurality ofhousings have to be produced in order to facilitate safe fixing of theactuator at a housing section that is typically associated with theinternal combustion engine.

Thus the publication document DE 10 2013 013 659 A1 discloses aconnection of an actuator with a housing section wherein a supportelement is configured to establish the connection wherein the retainingelement includes support elements and wherein the retaining element isarranged between a actuator cover and the housing section. Since theretaining element is received with its support elements between ahousing cover of the actuator and the housing section, the housingsection requires a recess that is configured specifically for theretaining element so that a safe connection is facilitated between thehousing and the housing section. This causes a comprehensive and thus acomplex and comprehensive of the housing section to the retainingelement.

BRIEF SUMMARY OF THE INVENTION

Thus, it is an object of the invention to provide an actuator for a camphaser which is attach able in a modular manner reliably and at lowcost. It is another object of the invention to provide a cam phaser thatimplements a reliable adjustment of the cam shaft.

The object is achieved according to the invention by an actuator for acam phaser, the cam phaser including a hydraulic valve that isadjustable by the actuator, wherein the actuator is receivable at ahousing section of a component that receives the cam phaser, wherein theactuator includes a retaining element and a housing with functionallyrelevant components, wherein the actuator is attached by the retainingelement at the housing section, wherein the retaining element isconfigured separate from the housing, wherein safe positioning of theactuator at the housing section is provided by a section of theretaining element that supports the actuator at the housing section in adirection of an axial orientation of the actuator, and wherein a housingcover of the housing is at least partially arranged between the sectionof the retaining element and the housing section.

The object is also achieved by a cam phaser including theelectromagnetic actuator described supra.

Advantageous embodiments with useful and nontrivial improvements of theinvention according to the invention are provided in the respectivedependent claims.

An actuator according to the invention for a cam phaser is configuredreceivable at a housing section of a unit receiving the cam phaser. Thecam phaser includes a hydraulic valve which is adjustable by theactuator. The actuator includes a retaining element to attach theactuator at the housing section, wherein the retaining element isconfigured separate from the actuator. According to the invention asection of the retaining element is formed that supports the actuator ina direction of its axial extension at the housing section in order toreliably position the actuator at the housing section, wherein a housingcover of the actuator is at least partially arranged between the sectionof the retaining element and the housing section. This means that theactuator is supported by the retaining element at the housing sectionwherein a longitudinal axial position of the actuator is secured inparticular. This means put differently that a functionally relevantsection of the actuator which includes in particular an adjustmentdevice for adjusting the piston and movement devices configured to causea movement of the adjustment device, e.g. configured as a magnetarrangement and an electrically flow able coil configured to generate amagnetic field can be produced separate from the retaining element thathas to be configured housing specific, wherein the housing specificactuator is provided as a combination of both components. Putdifferently the actuator is configured modular since the functionallyrelevant section can be produced separately from an attachment relevantsection of the actuator.

It is an advantage that the retaining element is configured housingspecific wherein however the functionally relevant section of theactuator which is enveloped by the housing cover does not have to beconfigured to provide fixing attachment at the housing section.

Thus the functionally relevant section of the actuator can be producedin high numbers since it is independent from the housing section and theretaining element fixing the functionally relevant section of theactuator of the housing section can be produced in a smaller numberspecific to the housing section.

Thus a secure housing section specific connection is implemented whereinthe functionally relevant section of the actuator can be produced inhigh volume and thus in a cost effective manner so that the entiremodular actuator, the functionally relevant section and the retainingelement, can be produced overall in a cost effective manner.

The modular configuration has the additional advantage of flexibleassembly which facilitates for example a quick attachment of theretaining element to proto types or production components.

The retaining element is configured for fixation at the housing sectionand can thus include receiving openings configured to receive fixingelements, e.g. bolts. By the same token it can include fixing devices inthe form of snap elements or it can be fixed by rotary form locking,e.g. by a bayonet closure at the housing section.

Secure joining of the functionally relevant section and the retainingelement can be provided in that the housing cover and the retainingelement are configured in an alternating manner as an outer boundarythat is oriented away from the housing section.

Thus a support of the housing cover and of the retaining element isimplemented in an alternating manner relative to the housing sectionwherein the retaining element as well as the housing cover and thus thehousing support each other in an alternating manner.

In another embodiment of the actuator according to the invention theretaining element is configured at least partially complementary to thehousing which yields another safe reception of the retaining element atthe housing cover and vice versa.

In another embodiment of the actuator according to the invention theretaining element is configured so that it envelops the housingessentially over its circumference, in particular over its envelopingsurface. This has the advantage that the actuator is flat in an axialdirection of the actuator longitudinal axis so that the actuator ischaracterized by small installation space requirement.

Advantageously the retaining element receives the actuator through formlocking in order to reliably attach the actuator at the housing section.

In another embodiment of the actuator according to the invention a snaplocking element is configured at the housing cover, advantageously at anenveloping surface of the housing so that a movement of the retainingelement in the axial direction is preventable. The snap locking elementprovides a safe connection between the functionally relevant section ofthe actuator and the retaining element so that a functionally relevantsection and the retaining element configured as a component can becaptured and positioned during an installation of the actuator at thehousing section. In another embodiment the retaining element isconfigured to receive a position element configured at the housing whichfacilitates a correct positioning of the retaining element about thehousing circumference. This in turn facilitates a correct positioning ofthe actuator at the housing section.

The positioning element is advantageously configured as a plug indevice, in particular its connection socket since the plug in device isprovided for supplying energy to the actuator and respective electricalcurrent conducting elements are provided at the housing section whereinthe electrically conducting elements are to be conducted by the plug indevice. This means put differently that the positioning element isconfigured to correctly position the actuator at the housing sectionwith respect to a circumference of the actuator. The position safety canalso be implemented in that the retaining element includes an electricalconnection of the plug in device.

The retaining element is produced in a cost effective manner by aninjection molding method, in particular from a plastic material.

The retaining element can be configured as a component that completelycovers the housing cover however it is sufficient for reliable and safereception of the functionally relevant section to configure theretaining element frame shaped, wherein weight savings are provided inaddition to a reduced material requirement that cuts costs.

Advantageously the housing section is a section of the internalcombustion engine, in particular of a cylinder head of the internalcombustion engine since short distances between the actuator and the camshaft to be adjusted can be provided which reduces reaction time andthus adjustment time.

A second aspect of the invention relates to a cam phaser with anelectromagnetic actuator. According to the invention the actuator isconfigured as described supra. Thus, a reliable cam phaser can beimplemented which provides a reliable adjustment of valve timing of theinternal combustion engine which includes the cam phaser according tothe invention. Since adjustment of valve timing influences fuel burn andthus emissions of the internal combustion engine a fuel burn andemissions reduced reliable internal combustion engine can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages features and details of the invention can be derivedfrom the subsequent description of advantageous embodiments and from thedrawing figures. The feature and feature combinations recited in thepreceding description and the feature and feature combinations recitedin the subsequent figure description and/or in the figures by themselvesare not only useable in the respectively stated combination but also inother combinations or by themselves without departing from the spiritand scope of the invention. Identical reference numerals are associatedwith identical or functionally equivalent elements. For reasons ofclarity it is possible that the elements are not provided with theirreference numeral in all figures without however losing theirassociation, wherein:

FIG. 1 illustrates an actuator according to the invention in a firstembodiment;

FIG. 2 illustrates the actuator according to FIG. 1 in a perceptivelyview;

FIG. 3 illustrates an actuator according to FIG. 1 in a sectional view;

FIG. 4 illustrates the actuator according to FIG. 1 with a retainingelement in a perspective view from below;

FIG. 5 illustrates the actuator according to FIG. 4 in a side view;

FIG. 6 illustrates the actuator according to FIG. 4 in a top view;

FIG. 7 illustrates a perspective top view of the retaining elementaccording to the first embodiment;

FIG. 8 illustrates a sectional detail view VIII of the actuator with theretaining element according to FIG. 4;

FIG. 9 illustrates a top view of the actuator according to the inventionwith the retaining element in a second embodiment;

FIG. 10 illustrates a perspective top view of the actuator with theretaining element according to FIG. 9;

FIG. 11 illustrates a perspective bottom view of the actuator accordingto FIG. 9.

FIG. 12 illustrates a top view of the retaining element according to thesecond embodiment;

FIG. 13 illustrates a side view of the retaining element according toFIG. 12

FIG. 14 illustrates a perspective top view of a detail XIV of theactuator according to FIG. 9;

FIG. 15 illustrates a top view of the actuator according to theinvention in a third embodiment;

FIG. 16 illustrates a side view of the actuator according to FIG. 15;

FIG. 17 illustrates a perspective top view of the actuator with itsretaining element in a fourth embodiment;

FIG. 18 illustrates a perspective top view of the actuator according tothe invention in a fifth embodiment;

FIG. 19 illustrates a side view of the actuator according to FIG. 18;

FIG. 20 illustrates a perspective top view of the retaining element ofthe actuator according to FIG. 18;

FIG. 21 illustrates a perspective view from below of the retainingelement according to FIG. 20; and

FIG. 22 illustrates a side view of the retaining element according toFIG. 20.

DETAILED DESCRIPTION OF THE INVENTION

A cam phaser that is not illustrated in detail is configured to adjust acam shaft. The cam phaser includes a hydraulic valve that is notillustrated in more detail which includes a piston that is notillustrated in more detail and which is moveable in particular in anaxial direction. In order to hydraulically supply the cam phaser pluralconnections are provided at a housing of the hydraulic valve thatreceives the piston. The housing is configured substantially tubular.

The cam phaser facilitates adjusting opening and closing timing of gascontrol valves of an internal combustion engine that includes a cylinderhead and which is not illustrated in more detail during operations.

Thus a relative angular orientation of a cam shaft that is rotate ablyreceived in the cylinder head of the internal combustion engine and notillustrated in more detail is continuously adjusted relative to a crankshaft of the internal combustion engine that is not illustrated in moredetail wherein the cam shaft is rotated relative to the crank shaft.Rotating the cam shaft moves the opening and closing timing of the gascontrol valves so that the internal combustion engine can developoptimum power at a respective speed.

A stator of the cam phaser is connected torque proof with a drive gearof the cam shaft. Insides of a stator base element include radiallyinward extending bars in uniform distances so that an intermediary spaceis formed between two respective adjacent bars. A vane of a rotor hub ofa rotor of the cam phaser is arranged so that it protrudes into theintermediary space. Corresponding to the number of intermediary spacesthe rotor hub includes a plurality of veins. Thus the veins divide eachintermediary space into pressure cavities. A pressure medium, typicallya hydraulic fluid is introduced into the intermediary spaces by thehydraulic valve in a controlled manner.

A pressure cavity is associated with each operating connection. Thus thefirst pressure cavity is associated with the first operating connectionand the second pressure cavity is associated with the second operatingconnection. In order to adjust an angular orientation between the camshaft and the crank shaft the pressure medium in the first pressurecavity or in the second pressure cavity is pressurized while the secondpressure cavity or the first pressure cavity is unloaded. The unloadingis performed through at least one tank connection, wherein the hydraulicfluid can drain through the tank connection.

The piston is moved by an actuator 10 which is configured in a firstembodiment according to FIGS. 1-8, wherein a move able plunger 12 of theactuator 10 c.f e.g. FIG. 11 is axially move able along a longitudinalaxis 14 of the actuator 10. The actuator 10 is configured as anelectromagnetic actuator. The actuator 10 includes a pole tube 24 thatis arranged within a cylindrical coil that generates a magnetic fieldand a housing 16. The housing 16 produced according to a plasticinjection molding method so that it is possible in a cost effectivemanner to fabricate the housing 16 and to simultaneously insert variouscomponents of a pole yoke which provides closed magnetic flux during theinjection molding method.

In order to provide the magnetic flux the coil is loadable with powerthrough a connection socket 18 that is received at the housing 16.

The actuator 10 is configured as a preassembled unit for attachment at ahousing section that is not illustrated in more detail. In theillustrated embodiments the actuator 10 is configured for attachment ata housing section of the cylinder head. This means put differently thatthe actuator 10 is attached at the cylinder head. By the same token thehousing section can also be a partial section of the cam phaser oranother component of the internal combustion engine.

In order to provide a reliable connection of the actuator 10 with thehousing section the housing section includes a retaining element 20 thatis independent from its function specific section wherein the retainingsection is used for moving the piston and is at least partiallyenveloped by the housing 16 wherein the retaining element supports thefunction specific section in a direction of its axial extension againstthe housing section.

The housing section 16 includes a coil that is not illustrated in moredetail which is received in a coil carrier 22. The coil carrier 22includes a pole tube 24 which is arranged between a housing cover 26 ofthe housing 16 and the coil carrier 22. A connection 28 configured tosupply electrical current to the coil is received in the connectionsocket 18 which extends at least in sections over a cover surface of thehousing cover 26.

The housing cover 26 includes a covering 32 which radially envelops apot shaped cover section 34. The covering 32 functions as a stop of thepreassembled actuator 10 during assembly at the housing section.

FIG. 4 illustrates the actuator 10 according to the invention in thefirst embodiment assembled with its retaining element 20. The retainingelement 20 which is illustrated by itself in FIG. 7 is frame shaped andincludes an opening 36 that is configured complementary to an envelopingsurface section 38 of the cover section 34. This means put differentlythat the cover element 20 is configured at least partially complementarywith the housing 16.

In order to fix the actuator 10 at the housing section the actuator ispositioned in a receiving opening that is provided in the housingsection, wherein the covering 32 advantageously contacts the housingsection with its first annular surface 40 that is oriented towards thehousing section. Subsequently the retaining element 20 is placed ontothe housing 16 wherein the cover section 34 is arranged in the opening36. In order to secure the retaining element 20 at the housing 16 a snaplocking element 42 is configured at the enveloping surface section 38 ofthe cover section 34 wherein the snap locking element is configured toprevent a movement of the support element 20 in the axial directionafter fixing the retaining element 20 at the housing section since theretaining element 20 is arranged in the portion of the snap lockingelement 42 quasi between the housing section and the housing 16.Advantageously two snap locking elements 42 are configured that arepositioned opposite to each other.

Thus, the housing cover 26 and the retaining element 20 are configuredin an alternating manner over a circumference of the actuator 10 as anouter border that is oriented away from the housing section. This meansput differently that a cover surface 44 defining the actuator 10 withits retaining element 20 relative to the ambient wherein the coversurface 44 is configured transversal to the longitudinal axis 14 isconfigured in an alternating manner by the housing cover 26 and theretaining element 20.

Another option to fix the actuator 10 at the housing section is toposition the function specific section of the actuator 10 in a firststep without the retaining element 20 in a predetermined receivingopening in the housing section. In order to fixate the actuator 10 atthe housing section the retaining element 20 is subsequently applied tothe housing 16 starting from the cover surface 30, wherein the coversection 34 is arranged in the opening 36. A second annular surface 53 ofthe covering 32 is arranged opposite to the first contact surface 54 andcontacts the contact surface 54 at least partially. The snap lockingelement 42 fixates the retaining element 20 at the housing 16 andthereafter the retaining element 20 is fixated at the housing section.

Thus the retaining element 20 is configured to envelop the housing 16,in particular the housing cover 26 along its circumference in particularalong its enveloping surface.

In order to receive the connection socket 18 the retaining element 20includes a recess 46 that is unlimited on one side and configuredtransversal in particular perpendicular to the opening 36 wherein therecess 46 supports the connection socket 18 with three of its lateralsurfaces 48. This means put differently that the retaining element 20 isconfigured to receive a plug in device 52 of the actuator 10 whichincludes the connection socket 18 and the connection 28.

In an embodiment that is not illustrated in more detail the two sidesurfaces 48 that are configured opposite to each other are provided withclamping elements protruding into the recess at edges 50 so that anadditional retaining safety of the retaining element 20 is provided atthe housing 16 in addition to the snap locking elements 42 before andduring the assembly of the actuator 10 at the housing section.

The retaining element 20 is configured as an injection molded componentin order to save weight and cost it is configured frame shaped andincludes recesses 56 which have a rather small wall thickness whereinstruts 58 are configured between the recesses 56 in order to providestability and strength to the retaining element 20 wherein a wallthickness of the retaining element 20 is increased at portions includingthe struts 58 compared to the wall thickness of the recesses 56.

In order to attach the actuator 10 at the housing section receivingopenings 60 are provided to receive attachment devices that are notillustrated in more detail which are configured to provide a fixingattachment of the actuator 10 at the housing section. The attachmentdevices can be provided in the form of bolts so that a disengage ableconnection of the actuator 10 with the housing section is provided. Ifthe retaining element 20 is provided as a low cost plastic component asit is the case in the instant embodiment metal sleeves 62 are arrangedin the receiving opening 60 so that a secure connection can beestablished. In the illustrated embodiment four receiving openings areprovided. More or fewer receiving openings can be arranged wherein thenumber of the receiving openings 60 is configured to provide safesupport of the actuator 10 at the housing section. Not every receivingopening 60 has to be used for attachment purposes. This can be handledin a flexible manner and can be adapted to the housing section.

FIG. 8 illustrates the actuator 10 with its retaining element 20 in adetail view VIII in cross section. The first contact surface 54 isarranged opposite to the second ring surface 53 and in contact therewithwherein the second contact surface 55 of the retaining element 20 isconfigured at a distance a from the first contact surface 54.Advantageously the distance A corresponds to a thickness D of the coverring 32 so that a flat contact of the actuator 10 can be configuredbetween the housing section and the actuator 10 and advantageously aseal element can be arranged between the housing section and theactuator 10.

FIGS. 9-14 illustrate the actuator 10 according to the invention in asecond embodiment. The retaining element 20 is configured substantiallyidentical to the retaining element 20 according to the first embodimentwherein the most significant distance is the reception or envelopment ofthe connection socket 18. Compared to the first embodiment of theactuator 10 according to the invention wherein the retaining element 20is configured to substantially envelop the connection socket 18 in thecircumferential direction. The retaining socket 18 of the secondembodiment is supported in a radial direction of the actuator 10. Thismeans put differently that an element section 64 of the retainingelement 20 configured to receive the connection socket 18 extends inaxial direction in circumferential direction and in radial direction.

The connection socket 18 includes a boss shaped lug 70 at its end 68that is arranged in a portion of the actuator center 66, wherein theboss shaped lug is received and supported in the element section 64. Thelug 70 can have different shapes. In the illustrated second embodimentthe lug includes a rectangular cross section. By the same token the lugcould also have a circular or oval or another cross section. Accordinglythe lug 46 is configured complementary to the cross section.

It is appreciated that the reception of the connection socket 18 or ofthe plug in device 52 in the retaining element 20 provides securepositioning of the actuator 10 at the housing section. This means putdifferently that a position of the actuator 10 relative to the housingsection can be safely provided by a positioning element that isconfigured at the housing 16 or at the retaining ring 20 wherein thepositioning element in the instant embodiment is the connection socket18 or the plug in device 52.

In FIGS. 15 and 16 the actuator 10 according to the invention isillustrated in a third embodiment. The connection socket 18 isconfigured in the portion of the lug 70 differently from the connectionsocket 18 of the second embodiment, wherein the lug 70 is configuredwithout distance between the cover surface 30. Thus as a protrusion in adirection of the longitudinal axis 14.

In FIGS. 17-22 which illustrate a fourth embodiment of the actuator 10according to the invention the connection socket 18 is enveloped by theretaining element 20. Put differently this means that the connectionsocket 18 is configured integrally in one piece together with theretaining element 20. Thus the retaining element 20 includes anelectrical connection of the plug in device 52. In order to supplyenergy and to correctly position the actuator 10 at the housing sectionthe connection 28 of the plug in device 52 is configured at the coversurface 30. When assembling the actuator 10 joining the connection witha connection plug that is not illustrated in more detail and which isconfigured complementary to the connection 28 and which is arranged inthe connection socket 18 configured at the support element 20 theconnection of the retaining element 20 at the housing 16 is stabilizedin addition to the snap lock connection implemented by the snap lockingelements 42.

Through the retaining element 20 the actuator 10 can be attached at thehousing section easily and can be disengaged from the housing section ina simple manner. Furthermore a seal element that is not illustrated inmore detail is arranged between the retaining element 20 and the housingsection. In the illustrated embodiment the actuator 10 is attached atthe housing section through a threaded connection. By the same token theretaining element 20 can include devices for establishing a snap lockedconnection and/or a rotary connection, in particular a bayonetconnection instead of the receiving opening 60.

REFERENCE NUMERALS AND DESIGNATIONS

-   -   10 actuator    -   12 plunger    -   14 longitudinal axis    -   16 housing    -   18 connection socket    -   20 retaining element    -   22 coil carrier    -   24 pole tube    -   26 housing cover    -   28 connection    -   30 cover surface    -   32 cover ring    -   34 cover section    -   36 opening    -   38 enveloping surface section    -   39 enveloping surface    -   40 first annular surface    -   42 snap locking element    -   44 cover surface    -   46 recess    -   48 lateral surface    -   50 edge    -   52 insertion device    -   53 second annular surface    -   54 first contact surface    -   55 second contact surface    -   56 recess    -   58 strut    -   60 receiving opening    -   62 metal sleeve    -   64 element section    -   66 actuator center    -   68 end    -   70 lug    -   A distance    -   D thickness

What is claimed is:
 1. An actuator for a cam phaser, the cam phasercomprising: a hydraulic valve that is adjustable by the actuator,wherein the actuator is receivable at a housing section of a componentthat receives the cam phaser, wherein the actuator includes a retainingelement and a housing with functionally relevant components, wherein theactuator is attached by the retaining element at the housing section,wherein the retaining element is configured separate from the housing,wherein safe positioning of the actuator at the housing section isprovided by a section of the retaining element that supports theactuator at the housing section in a direction of an axial orientationof the actuator, and wherein a housing cover of the housing is at leastpartially arranged between the section of the retaining element and thehousing section.
 2. The actuator according to claim 1, wherein thehousing cover and the retaining element are arranged in an alternatingmanner along a circumference of the housing as an outer boundary that isoriented away from the housing section.
 3. The actuator according toclaim 1, wherein the retaining element is at least partiallycomplementary to the housing.
 4. The actuator according to claim 1,wherein the retaining element envelops the housing essentially alongcircumference of the housing and along an enveloping surface of thehousing.
 5. The actuator according to claim 1, wherein the retainingelement receives the housing in a form locking manner.
 6. The actuatoraccording to claim 1, wherein the retaining element includes a contactsurface that is arranged transversal to a receiving direction of theactuator, and wherein the contact surface is arranged opposite to and incontact with a housing surface.
 7. The actuator according to claim 1,wherein a snap locking element is arranged at an enveloping surface ofthe housing, wherein the snap locking element is configured to prevent amovement of the retaining element in the axial direction.
 8. Theactuator according to claim 1, wherein the retaining element isconfigured to receive a positioning element that is arranged at thehousing.
 9. The actuator according to claim 1, wherein the retainingelement receives a plug-in device of the actuator at least partially.10. The actuator according to claim 1, wherein the retaining element isconfigured as an injection molded component.
 11. The actuator accordingto claim 9, wherein the retaining element includes an electricalconnection of the plug-in device.
 12. The actuator according to claim 1,wherein the retaining element is attachable at the housing section in adisengageable manner.
 13. The actuator according to claim 1, wherein theretaining element is configured as a frame.
 14. The actuator accordingto claim 1, wherein the housing section is a section of a cylinder headof an internal combustion engine.
 15. A cam phaser, comprising: theelectromagnetic actuator according to claim 1.